All slot providers

A slot provider (studio) designs and builds the game itself — the math, the art, the bonus mechanics. An online casino is the operator that distributes it: they handle the cashier, licensing, and player account but don't make the games themselves. A single game like Book of Dead is built by Play'n GO and then served at hundreds of different casinos.

Often yes. Many slots ship in 2–4 RTP configurations (e.g., 96.5% / 96% / 94% / 92%) and the operator picks one at integration. You can always verify the specific RTP from a game's in-demo info screen. On SlotsBrothers, the demo build uses whatever version SlotsLaunch distributes — typically the provider's default.

Pragmatic Play (Gates of Olympus, Sweet Bonanza, Big Bass Bonanza), NetEnt (Starburst, Gonzo's Quest), Play'n GO (Book of Dead, Reactoonz), and Playtech (Age of the Gods) lead in player volume across most European markets. Newer challengers like Nolimit City, Hacksaw Gaming and Push Gaming punch above their weight in the streaming / high-volatility niche.

Yes, byte-for-byte. Same RNG, same RTP, same volatility profile, same bonus probabilities. The only difference is that you're betting virtual credits that reset on reload rather than real money.